[PATCH] D49337: Skip debuginfo intrinsic in markLiveBlocks.

[Xin Tong via Phabricator via llvm-commits]

trentxintong added a comment.

Hi @hfinkel.

Thank you for taking a look at this code. I agree we should definitely "else" the StoreInst check and I have observed improvements in Xcode Instrument for doing so.

And I should also move the DbgInfoIntrinsic check inside the IntrinsicInst check by comparing IntrinsicID.

The problem with moving the IntrinsicInst checks inside the dyn_cast<CallInst> is that every intrinsic call will need to go through a dyn_cast<CallInst> check, a getCalledValue() and then a dyn_cast<Function>(CalledValue) check.  If we have a lot of intrinsic which we do when compiling with debuginfo, we could end up being overall slower than keeping the IntrinsicInst check.

When we compile without debuginfo, moving the intrinsic check inside the CallInst check will not necessarily bring us performance, as now every CallInst needs to checks for the existing cases in the if (dyn_cast<CallInst>)) and the Intrinsics (which require dyn_cast<Function>(CalledValue)).

Right now I am seeing the version which we keep the IntrinsicInst check and adding the DbgInfoIntrinsic inside it to be the fastest on sqlite3.c with debuginfo.


Repository:
  rL LLVM

https://reviews.llvm.org/D49337